PHP8

Behavioral/ChainOfResponsibilities/Handler.php

@@ -6,11 +6,8 @@ use Psr\Http\Message\RequestInterface;
 
 abstract class Handler
 {
-    private ?Handler $successor = null;
-
-    public function __construct(Handler $handler = null)
+    public function __construct(private ?Handler $successor = null)
     {
-        $this->successor = $handler;
     }
 
     /**

Behavioral/ChainOfResponsibilities/Responsible/HttpInMemoryCacheHandler.php

@@ -7,13 +7,9 @@ use Psr\Http\Message\RequestInterface;
 
 class HttpInMemoryCacheHandler extends Handler
 {
-    private array $data;
-
-    public function __construct(array $data, ?Handler $successor = null)
+    public function __construct(private array $data, ?Handler $successor = null)
     {
         parent::__construct($successor);
-
-        $this->data = $data;
     }
 
     protected function processing(RequestInterface $request): ?string

Behavioral/Command/AddMessageDateCommand.php

@@ -8,15 +8,12 @@ namespace DesignPatterns\Behavioral\Command;
  */
 class AddMessageDateCommand implements UndoableCommand
 {
-    private Receiver $output;
-
     /**
      * Each concrete command is built with different receivers.
      * There can be one, many or completely no receivers, but there can be other commands in the parameters.
      */
-    public function __construct(Receiver $console)
+    public function __construct(private Receiver $output)
     {
-        $this->output = $console;
     }
 
     /**

Behavioral/Command/HelloCommand.php

@@ -8,15 +8,12 @@ namespace DesignPatterns\Behavioral\Command;
  */
 class HelloCommand implements Command
 {
-    private Receiver $output;
-
     /**
      * Each concrete command is built with different receivers.
      * There can be one, many or completely no receivers, but there can be other commands in the parameters
      */
-    public function __construct(Receiver $console)
+    public function __construct(private Receiver $output)
     {
-        $this->output = $console;
     }
 
     /**

Behavioral/Iterator/Book.php

@@ -4,13 +4,8 @@ namespace DesignPatterns\Behavioral\Iterator;
 
 class Book
 {
-    private string $author;
-    private string $title;
-
-    public function __construct(string $title, string $author)
+    public function __construct(private string $title, private string $author)
     {
-        $this->author = $author;
-        $this->title = $title;
     }
 
     public function getAuthor(): string

Behavioral/Mediator/UserRepositoryUiMediator.php

@@ -4,14 +4,8 @@ namespace DesignPatterns\Behavioral\Mediator;
 
 class UserRepositoryUiMediator implements Mediator
 {
-    private UserRepository $userRepository;
-    private Ui $ui;
-
-    public function __construct(UserRepository $userRepository, Ui $ui)
+    public function __construct(private UserRepository $userRepository, private Ui $ui)
     {
-        $this->userRepository = $userRepository;
-        $this->ui = $ui;
-
         $this->userRepository->setMediator($this);
         $this->ui->setMediator($this);
     }

Behavioral/Memento/Memento.php

@@ -4,11 +4,8 @@ namespace DesignPatterns\Behavioral\Memento;
 
 class Memento
 {
-    private State $state;
-
-    public function __construct(State $stateToSave)
+    public function __construct(private State $state)
     {
-        $this->state = $stateToSave;
     }
 
     public function getState(): State

Behavioral/Memento/State.php

@@ -4,7 +4,7 @@ namespace DesignPatterns\Behavioral\Memento;
 
 use InvalidArgumentException;
 
-class State
+class State implements \Stringable
 {
     const STATE_CREATED = 'created';
     const STATE_OPENED = 'opened';

Behavioral/NullObject/Service.php

@@ -4,11 +4,8 @@ namespace DesignPatterns\Behavioral\NullObject;
 
 class Service
 {
-    private Logger $logger;
-
-    public function __construct(Logger $logger)
+    public function __construct(private Logger $logger)
     {
-        $this->logger = $logger;
     }
 
     /**

Behavioral/Observer/User.php

@@ -12,7 +12,6 @@ use SplObserver;
  */
 class User implements SplSubject
 {
-    private string $email;
     private SplObjectStorage $observers;
 
     public function __construct()
@@ -32,7 +31,6 @@ class User implements SplSubject
 
     public function changeEmail(string $email)
     {
-        $this->email = $email;
         $this->notify();
     }
 

Behavioral/Specification/Item.php

@@ -4,11 +4,8 @@ namespace DesignPatterns\Behavioral\Specification;
 
 class Item
 {
-    private float $price;
-
-    public function __construct(float $price)
+    public function __construct(private float $price)
     {
-        $this->price = $price;
     }
 
     public function getPrice(): float

Behavioral/Specification/NotSpecification.php

@@ -4,11 +4,8 @@ namespace DesignPatterns\Behavioral\Specification;
 
 class NotSpecification implements Specification
 {
-    private Specification $specification;
-
-    public function __construct(Specification $specification)
+    public function __construct(private Specification $specification)
     {
-        $this->specification = $specification;
     }
 
     public function isSatisfiedBy(Item $item): bool

Behavioral/Specification/PriceSpecification.php

@@ -4,13 +4,8 @@ namespace DesignPatterns\Behavioral\Specification;
 
 class PriceSpecification implements Specification
 {
-    private ?float $maxPrice;
-    private ?float $minPrice;
-
-    public function __construct(?float $minPrice, ?float $maxPrice)
+    public function __construct(private ?float $minPrice, private ?float $maxPrice)
     {
-        $this->minPrice = $minPrice;
-        $this->maxPrice = $maxPrice;
     }
 
     public function isSatisfiedBy(Item $item): bool

Behavioral/Strategy/Comparator.php

@@ -7,8 +7,6 @@ interface Comparator
     /**
      * @param mixed $a
      * @param mixed $b
-     *
-     * @return int
      */
     public function compare($a, $b): int;
 }

Behavioral/Strategy/Context.php

@@ -4,11 +4,8 @@ namespace DesignPatterns\Behavioral\Strategy;
 
 class Context
 {
-    private Comparator $comparator;
-
-    public function __construct(Comparator $comparator)
+    public function __construct(private Comparator $comparator)
     {
-        $this->comparator = $comparator;
     }
 
     public function executeStrategy(array $elements): array

Behavioral/Visitor/Group.php

@@ -4,11 +4,8 @@ namespace DesignPatterns\Behavioral\Visitor;
 
 class Group implements Role
 {
-    private string $name;
-
-    public function __construct(string $name)
+    public function __construct(private string $name)
     {
-        $this->name = $name;
     }
 
     public function getName(): string

Behavioral/Visitor/User.php

@@ -4,11 +4,8 @@ namespace DesignPatterns\Behavioral\Visitor;
 
 class User implements Role
 {
-    private string $name;
-
-    public function __construct(string $name)
+    public function __construct(private string $name)
     {
-        $this->name = $name;
     }
 
     public function getName(): string

Creational/AbstractFactory/Tests/AbstractFactoryTest.php

@@ -21,8 +21,6 @@ class AbstractFactoryTest extends TestCase
 
     /**
      * @dataProvider provideFactory
-     *
-     * @param WriterFactory $writerFactory
      */
     public function testCanCreateCsvWriterOnUnix(WriterFactory $writerFactory)
     {

Creational/Builder/Parts/Vehicle.php

@@ -4,13 +4,7 @@ namespace DesignPatterns\Creational\Builder\Parts;
 
 abstract class Vehicle
 {
-    /**
-     * @var object[]
-     */
-    private array $data = [];
-
     public function setPart(string $key, object $value)
     {
-        $this->data[$key] = $value;
     }
 }

Creational/FactoryMethod/FileLogger.php

@@ -4,11 +4,8 @@ namespace DesignPatterns\Creational\FactoryMethod;
 
 class FileLogger implements Logger
 {
-    private string $filePath;
-
-    public function __construct(string $filePath)
+    public function __construct(private string $filePath)
     {
-        $this->filePath = $filePath;
     }
 
     public function log(string $message)

Creational/FactoryMethod/FileLoggerFactory.php

@@ -4,11 +4,8 @@ namespace DesignPatterns\Creational\FactoryMethod;
 
 class FileLoggerFactory implements LoggerFactory
 {
-    private string $filePath;
-
-    public function __construct(string $filePath)
+    public function __construct(private string $filePath)
     {
-        $this->filePath = $filePath;
     }
 
     public function createLogger(): Logger

Creational/Pool/StringReverseWorker.php

@@ -6,11 +6,8 @@ use DateTime;
 
 class StringReverseWorker
 {
-    private DateTime $createdAt;
-
     public function __construct()
     {
-        $this->createdAt = new DateTime();
     }
 
     public function run(string $text)

Creational/Singleton/Singleton.php

@@ -28,13 +28,6 @@ final class Singleton
     {
     }
 
-    /**
-     * prevent the instance from being cloned (which would create a second instance of it)
-     */
-    private function __clone()
-    {
-    }
-
     /**
      * prevent from being unserialized (which would create a second instance of it)
      */

Dockerfile

@@ -1,11 +1,15 @@
 FROM composer AS composer
 WORKDIR /app
 ADD . /app
-RUN composer install \
-    && ./vendor/bin/phpcs --ignore=_build . \
-    && ./vendor/bin/phpunit \
-    && ./vendor/bin/psalm --show-info=false \
-    && ./check-refs-readmes
+RUN composer install
+
+FROM php:8-cli-alpine
+WORKDIR /app
+COPY --from=composer /app /app
+RUN ./vendor/bin/phpcs --ignore=_build . \
+        && ./vendor/bin/phpunit \
+        && ./vendor/bin/psalm --show-info=false \
+        && ./check-refs-readmes
 
 FROM python AS sphinx_build
 WORKDIR /app

More/EAV/Attribute.php

@@ -4,15 +4,13 @@ namespace DesignPatterns\More\EAV;
 
 use SplObjectStorage;
 
-class Attribute
+class Attribute implements \Stringable
 {
     private SplObjectStorage $values;
-    private string $name;
 
-    public function __construct(string $name)
+    public function __construct(private string $name)
     {
         $this->values = new SplObjectStorage();
-        $this->name = $name;
     }
 
     public function addValue(Value $value)

More/EAV/Entity.php

@@ -4,7 +4,7 @@ namespace DesignPatterns\More\EAV;
 
 use SplObjectStorage;
 
-class Entity
+class Entity implements \Stringable
 {
     /**
      * @var SplObjectStorage<Value,Value>
@@ -12,19 +12,11 @@ class Entity
     private $values;
 
     /**
-     * @var string
-     */
-    private string $name;
-
-    /**
-     * @param string $name
      * @param Value[] $values
      */
-    public function __construct(string $name, $values)
+    public function __construct(private string $name, $values)
     {
-        /** @var SplObjectStorage<Value,Value> values */
         $this->values = new SplObjectStorage();
-        $this->name = $name;
 
         foreach ($values as $value) {
             $this->values->attach($value);

More/EAV/Value.php

@@ -2,16 +2,10 @@
 
 namespace DesignPatterns\More\EAV;
 
-class Value
+class Value implements \Stringable
 {
-    private Attribute $attribute;
-    private string $name;
-
-    public function __construct(Attribute $attribute, string $name)
+    public function __construct(private Attribute $attribute, private string $name)
     {
-        $this->name = $name;
-        $this->attribute = $attribute;
-
         $attribute->addValue($this);
     }
 

More/Repository/Domain/Post.php

@@ -4,11 +4,6 @@ namespace DesignPatterns\More\Repository\Domain;
 
 class Post
 {
-    private PostId $id;
-    private PostStatus $status;
-    private string $title;
-    private string $text;
-
     public static function draft(PostId $id, string $title, string $text): Post
     {
         return new self(
@@ -29,12 +24,12 @@ class Post
         );
     }
 
-    private function __construct(PostId $id, PostStatus $status, string $title, string $text)
-    {
-        $this->id = $id;
-        $this->status = $status;
-        $this->text = $text;
-        $this->title = $title;
+    private function __construct(
+        private PostId $id,
+        private PostStatus $status,
+        private string $title,
+        private string $text
+    ) {
     }
 
     public function getId(): PostId

More/Repository/Domain/PostId.php

@@ -13,8 +13,6 @@ use InvalidArgumentException;
  */
 class PostId
 {
-    private int $id;
-
     public static function fromInt(int $id): PostId
     {
         self::ensureIsValid($id);
@@ -22,9 +20,8 @@ class PostId
         return new self($id);
     }
 
-    private function __construct(int $id)
+    private function __construct(private int $id)
     {
-        $this->id = $id;
     }
 
     public function toInt(): int

More/Repository/Domain/PostStatus.php

@@ -21,9 +21,6 @@ class PostStatus
         self::STATE_PUBLISHED_ID => self::STATE_PUBLISHED,
     ];
 
-    private int $id;
-    private string $name;
-
     public static function fromInt(int $statusId)
     {
         self::ensureIsValidId($statusId);
@@ -43,10 +40,8 @@ class PostStatus
         return new self($state, $status);
     }
 
-    private function __construct(int $id, string $name)
+    private function __construct(private int $id, private string $name)
     {
-        $this->id = $id;
-        $this->name = $name;
     }
 
     public function toInt(): int

More/Repository/PostRepository.php

@@ -17,11 +17,8 @@ use DesignPatterns\More\Repository\Domain\PostId;
  */
 class PostRepository
 {
-    private Persistence $persistence;
-
-    public function __construct(Persistence $persistence)
+    public function __construct(private Persistence $persistence)
     {
-        $this->persistence = $persistence;
     }
 
     public function generateId(): PostId

Structural/Adapter/EBookAdapter.php

@@ -8,11 +8,8 @@ namespace DesignPatterns\Structural\Adapter;
  */
 class EBookAdapter implements Book
 {
-    protected EBook $eBook;
-
-    public function __construct(EBook $eBook)
+    public function __construct(protected EBook $eBook)
     {
-        $this->eBook = $eBook;
     }
 
     /**

Structural/Bridge/Service.php

@@ -4,11 +4,8 @@ namespace DesignPatterns\Structural\Bridge;
 
 abstract class Service
 {
-    protected Formatter $implementation;
-
-    public function __construct(Formatter $printer)
+    public function __construct(protected Formatter $implementation)
     {
-        $this->implementation = $printer;
     }
 
     public function setImplementation(Formatter $printer)

Structural/Composite/Form.php

@@ -27,9 +27,7 @@ class Form implements Renderable
             $formCode .= $element->render();
         }
 
-        $formCode .= '</form>';
-
-        return $formCode;
+        return $formCode . '</form>';
     }
 
     public function addElement(Renderable $element)

Structural/Composite/TextElement.php

@@ -4,11 +4,8 @@ namespace DesignPatterns\Structural\Composite;
 
 class TextElement implements Renderable
 {
-    private string $text;
-
-    public function __construct(string $text)
+    public function __construct(private string $text)
     {
-        $this->text = $text;
     }
 
     public function render(): string

Structural/DataMapper/StorageAdapter.php

@@ -4,16 +4,11 @@ namespace DesignPatterns\Structural\DataMapper;
 
 class StorageAdapter
 {
-    private array $data = [];
-
-    public function __construct(array $data)
+    public function __construct(private array $data)
     {
-        $this->data = $data;
     }
 
     /**
-     * @param int $id
-     *
      * @return array|null
      */
     public function find(int $id)

Structural/DataMapper/User.php

@@ -4,9 +4,6 @@ namespace DesignPatterns\Structural\DataMapper;
 
 class User
 {
-    private string $username;
-    private string $email;
-
     public static function fromState(array $state): User
     {
         // validate state before accessing keys!
@@ -17,12 +14,8 @@ class User
         );
     }
 
-    public function __construct(string $username, string $email)
+    public function __construct(private string $username, private string $email)
     {
-        // validate parameters before setting them!
-
-        $this->username = $username;
-        $this->email = $email;
     }
 
     public function getUsername(): string

Structural/DataMapper/UserMapper.php

@@ -6,11 +6,8 @@ use InvalidArgumentException;
 
 class UserMapper
 {
-    private StorageAdapter $adapter;
-
-    public function __construct(StorageAdapter $storage)
+    public function __construct(private StorageAdapter $adapter)
     {
-        $this->adapter = $storage;
     }
 
     /**

Structural/Decorator/BookingDecorator.php

@@ -4,10 +4,7 @@ namespace DesignPatterns\Structural\Decorator;
 
 abstract class BookingDecorator implements Booking
 {
-    protected Booking $booking;
-
-    public function __construct(Booking $booking)
+    public function __construct(protected Booking $booking)
     {
-        $this->booking = $booking;
     }
 }

Structural/DependencyInjection/DatabaseConfiguration.php

@@ -4,17 +4,12 @@ namespace DesignPatterns\Structural\DependencyInjection;
 
 class DatabaseConfiguration
 {
-    private string $host;
-    private int $port;
-    private string $username;
-    private string $password;
-
-    public function __construct(string $host, int $port, string $username, string $password)
-    {
-        $this->host = $host;
-        $this->port = $port;
-        $this->username = $username;
-        $this->password = $password;
+    public function __construct(
+        private string $host,
+        private int $port,
+        private string $username,
+        private string $password
+    ) {
     }
 
     public function getHost(): string

Structural/DependencyInjection/DatabaseConnection.php

@@ -4,11 +4,8 @@ namespace DesignPatterns\Structural\DependencyInjection;
 
 class DatabaseConnection
 {
-    private DatabaseConfiguration $configuration;
-
-    public function __construct(DatabaseConfiguration $config)
+    public function __construct(private DatabaseConfiguration $configuration)
     {
-        $this->configuration = $config;
     }
 
     public function getDsn(): string

Structural/Facade/Facade.php

@@ -4,13 +4,8 @@ namespace DesignPatterns\Structural\Facade;
 
 class Facade
 {
-    private OperatingSystem $os;
-    private Bios $bios;
-
-    public function __construct(Bios $bios, OperatingSystem $os)
+    public function __construct(private Bios $bios, private OperatingSystem $os)
     {
-        $this->bios = $bios;
-        $this->os = $os;
     }
 
     public function turnOn()

Structural/FluentInterface/Sql.php

@@ -2,7 +2,7 @@
 
 namespace DesignPatterns\Structural\FluentInterface;
 
-class Sql
+class Sql implements \Stringable
 {
     private array $fields = [];
     private array $from = [];

Structural/Flyweight/Character.php

@@ -12,11 +12,8 @@ class Character implements Text
      * Any state stored by the concrete flyweight must be independent of its context.
      * For flyweights representing characters, this is usually the corresponding character code.
      */
-    private string $name;
-
-    public function __construct(string $name)
+    public function __construct(private string $name)
     {
-        $this->name = $name;
     }
 
     public function render(string $font): string

Structural/Flyweight/Word.php

@@ -4,11 +4,8 @@ namespace DesignPatterns\Structural\Flyweight;
 
 class Word implements Text
 {
-    private string $name;
-
-    public function __construct(string $name)
+    public function __construct(private string $name)
     {
-        $this->name = $name;
     }
 
     public function render(string $font): string

Structural/Proxy/HeavyBankAccount.php

@@ -20,6 +20,6 @@ class HeavyBankAccount implements BankAccount
         // years and decades ago must be fetched from a database or web service
         // and the balance must be calculated from it
 
-        return (int) array_sum($this->transactions);
+        return array_sum($this->transactions);
     }
 }

Structural/Registry/Tests/RegistryTest.php

@@ -5,15 +5,11 @@ namespace DesignPatterns\Structural\Registry\Tests;
 use InvalidArgumentException;
 use DesignPatterns\Structural\Registry\Registry;
 use DesignPatterns\Structural\Registry\Service;
-use PHPUnit\Framework\MockObject\MockObject;
 use PHPUnit\Framework\TestCase;
 
 class RegistryTest extends TestCase
 {
-    /**
-     * @var Service
-     */
-    private MockObject $service;
+    private Service $service;
 
     protected function setUp(): void
     {

composer.json

@@ -10,7 +10,7 @@
     ],
     "minimum-stability": "stable",
     "require": {
-        "php": ">=7.4",
+        "php": ">=8.0",
         "psr/http-message": "^1.0",
         "ext-json": "*"
     },
@@ -18,7 +18,7 @@
         "phpunit/phpunit": "^9",
         "squizlabs/php_codesniffer": "^3",
         "flyeralarm/php-code-validator": "^2.2",
-        "vimeo/psalm": "^3",
+        "vimeo/psalm": "^4",
         "psalm/plugin-phpunit": "*",
         "rector/rector": "*"
     },

psalm.xml

@@ -37,7 +37,6 @@
         <MissingReturnType errorLevel="info"/>
         <MissingPropertyType errorLevel="info"/>
         <InvalidDocblock errorLevel="info"/>
-        <MisplacedRequiredParam errorLevel="info"/>
 
         <PropertyNotSetInConstructor errorLevel="info"/>
         <MissingConstructor errorLevel="info"/>